Bicycle frame



FIG. 1 is a front-left perspective view of a bicycle frame.

FIG. 2 is a front elevation view thereof.

FIG. 3 is a rear elevation view thereof.

FIG. 4 is a left elevation view thereof.

FIG. 5 is a right elevation view thereof.

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom view thereof.

In all figures, broken lines illustrate environmental structures and form no part of the claimed design. 

CLAIM We claim the ornamental design for a bicycle frame, as shown and described. 